ANALYSIS METHODOLOGY OF RUBBER FRACTION IN FINE PARTICLES

A group of 11 global tire manufacturing companies initiated an environmental, health and ecological research program called the Tire Industry Project (TIP) in 2005. Bridgestone Corporation as one of the TIP members is pursuing research on behalf of TIP with the objective of quantifying the contribution of tire wear particles in total suspended particulate matter and other environmental media including sediment and soil. A method developed for quantifying rubber content in aerosol particles using Pyrolysis-GC-MS was presented at the Fall 172nd Technical Meeting of the Rubber Division of the American Chemical Society, Inc. It has been established that markers are required for tire tread particle quantification in the environment, and that one of the most promising methods is analysis of pyrolized polymer contained in the particulate matter. The goal of this study is to determine whether polymer concentrations quantified using this method are valid and reliable markers for tire tread particles in environmental media including sediment and soil.

Samples spiked with tire tread particles were prepared by mixing various proportions of tire particles and "standard' soil and used in the validation process. The tread particles were prepared in a laboratory by cryogenic grinding of new rubber and sieved for selection of a size range of 100~200mm.  Good correlation between the theoretical and estimated value was observed in spite of some scattering in the results.  With some improvements in preparing calibration curves, this method could be considered as valid for tire marker analysis in environmental media.